The present invention relates to a tire vulcanizing press which presses to fasten an upper and a lower molds used for vulcanizing a tire by hydraulic cylinders and raises and lowers the upper mold in an up-and-down direction to remove the tire being finished a vulcanizing processing.
There have been known this type of various tire vulcanizing presses which presses to fasten an upper and a lower molds used for vulcanizing a tire by hydraulic cylinders and raises and lowers the upper mold in an up-and-down direction to remove the tire being finished a vulcanizing processing. If classified in view of a press frame receiving a reaction force from a hydraulic fastening cylinder, they are chiefly classified into a rectangular frame type and a dome lock type. Already known ones as a rectangular frame type are disclosed in Japanese Unexamined Patent Application No. SHO 59-12827, Japanese Unexamined Patent Application No. SHO 61-134210, and Japanese Unexamined Patent Application No. SHO 63-118209This rectangular frame type requires a firm frame construction sufficient to receive a reaction force from the hydraulic fastening cylinder and a transmission member disposed retractably to support the reaction force between the upper mold and the press frame.
Therefore, to simplify the frame construction and omit the supporting member, the dome lock type is constituted such that the upper and the lower molds are accommodated in an upper and lower domes provided to be opened or closed so that the upper and the lower molds can be pressed in the upper and the lower domes. Already known ones as a dome lock type are disclosed in Japanese Unexamined Patent Application No. SHO 56-161139 and Japanese Unexamined Patent Application No. SHO 59-138432.
Next, referring to FIG. 6, a dome lock type tire vulcanizing press which is disclosed in above Japanese Unexamined Patent Application No. SHO 59-138432 is explained. A reference numeral 1 denotes a lower mold, and a reference numeral 2 denotes an upper mold. A reference numeral 3 denotes a lower mold installation member such as a lower platen, and a reference numeral 4 denotes an upper mold installation member such as an upper platen. And further, a reference numeral 5 denotes a lower dome, and a reference numeral 6 denotes an upper dome. A reference numeral 7 denotes a lock device, and a reference numeral 8 denotes a fastening cylinder. Moreover, a reference numeral 9 denotes a raise/lower cylinder, and a reference numeral 10 denotes a base frame. A reference numeral 11 denotes a stand frame, and a reference numeral 12 denotes a mold height adjusting device.
The lower mold 1 is installed on the lower mold installation member 3 by means of bolts etc. And, the lower mold installation member 3 is fixed on the base frame 10 by supporting rods 13, the fastening cylinder. The upper mold 2 is installed on the upper mold installation member 4 by means of bolts etc. And, the upper mold installation member 4 is fixed on the upper dome 6 through the mold height adjusting device 12 (which absorbs height difference between the upper mold 2 and the lower mold 1 in the case that the upper mold 2 and the lower mold 1 are formed in such a manner that either one has a taller height than the other).
The lower dome 5 is provided to be slightly raised or lowered by being guided by the supporting rods 13. The fastening cylinder 8 is installed on the lower surface of the lower dome 5, and a cylinder rod 8a is connected to the lower mold installation member 3. The upper dome 6 is installed on a lateral frame 14, and the lateral frame 14 is guided by the stand frame 11. The raise/lower cylinder 9 is connected to the stand frame 11. The lock device 7 is a means for connecting or disconnecting the upper dome 6 and the lower dome 5, and for example a bayonet-lock is used as this lock device 7.
The following is an explanation of an operation of above-described dome lock type tire vulcanizing press. First of all, an opening and closing operation is explained. If the raise/lower cylinder 9 is extended when the lock device 7 is in a disengaging condition, the lateral frame 14 rises by being guided by the stand frame 11. And, the upper dome 6, the upper mold installation member 4 and the upper mold 2 are positioned at their raised positions as shown by a two-dot long and two short dashes line so that an installation of a green tire or taking-out of the molded tire can be carried out. To the contrary, if the raise/lower cylinder 9 is contracted, the upper dome 6 is positioned at a solid line. And, a closing operation is finished by connecting the upper and the lower domes 5 and 6 by means of the lock device 7.
Next, a fastening operation of the upper and the lower molds 1, 2 is explained. When a pressurized oil is supplied into a port a of the fastening cylinder 8, the lower dome 5 connected to the fastening cylinder 8 is pressed toward a downward direction. The upper dome 6 is connected to the lower dome 5 by the lock-device 7, therefore the upper dome 6, the upper mold installation member 4; i.e. the upper mold 2, are lowered together, so that a pressurization can be performed between the upper and the lower molds 1, 2.
In the dome lock type tire vulcanizing press, since the upper mold installation member 4 is accommodated in the cylindrical dome 6, there is no maintenance space for maintaining heated vapor pipes of the upper and the lower platens. Therefore, there was a problem such that a maintenance work is difficult. Moreover, it was necessary to make the upper and the lower domes 5 and 6 to be thick so as to support the upper and the lower molds 1, 2. Therefore, there was a problem such that a tire vulcanizing press needs to increase its apparatus size as a whole. Especially, as shown in the drawing, in the case that there are provided a pair of right and left molds, it is necessary to keep a significant distance between the right and left molds in order to prevent the upper and the lower domes 5, 6 and the lock device 7.